Overview:

This mono-black deck revolves around Ob Nixilis, the Fallen, leveraging aggressive landfall triggers to amplify commander damage while draining opponents. The strategy focuses on turbo-land deployment using premium fetchlands, land recursion (Crucible of Worlds), and explosive mana generators (Cabal Coffers + Urborg, Tomb of Yawgmoth). Ob Nixilis serves as the primary win condition, supported by backup plans like Hatred-enabled commander-damage kills, Field of the Dead token swarms, and planeswalker-based attrition (Ugin, the Spirit Dragon, Karn Liberated). The deck employs high-tier tutors and card advantage engines to maintain momentum but lacks infinite combos, relying on incremental value and combat pressure.

Primer:

Core Strategy Execution:

1. Early Setup (Turns 1-3): Prioritize land-fetching artifacts (Expedition Map, Wayfarer's Bauble), mana acceleration (Sol Ring, Mox Diamond), and critical lands (Urborg, Tomb of Yawgmoth, Nykthos, Shrine to Nyx). Cast Ob Nixilis as early as Turn 3 using Jet Medallion or fast mana.
2. Landfall Triggers (Turns 4-6): Chain fetchland activations with Crucible of Worlds or Ancient Tomb-powered plays to trigger Ob Nixilis 2-3 times per turn cycle. Deploy Field of the Dead with Thespian's Stage copying it for exponential zombie production.
3. Win Execution (Turns 5-8):
   • Commander Burst: Cast Hatred with Ob Nixilis at 7+ power for a 21-damage lethal strike.
   • Life Drain: Stack landfall triggers with Retreat to Hagra and Ob Nixilis, the Hate-Twisted for incremental life loss.
   • Planeswalker Ultimates: Resolve Ugin, the Spirit Dragon's -10 or Karn Liberated's restart with a dominant board.

Mulligan Priorities:

• Keep hands with 2-3 lands, at least one fetchland or land tutor.
• Prioritize early acceleration (Mox Diamond, Sol Ring) or critical land enablers (Urborg, Coffers).
• Avoid hands lacking black mana sources or with only high-CMC threats.

Key Tips:

• Use Scroll Rack with fetchlands to manipulate landfall triggers.
• Deserted Temple doubles Nykthos/Cabal Coffers output for explosive turns.
• Phyrexian Tower sacrifices zombie tokens from Field of the Dead for instant-speed Ob Nixilis pumps.
• Shadowspear ensures trample/lifelink for Ob Nixilis while stripping opponents' hexproof/indestructible.

Weaknesses:

Critical

• Commander-dependent strategy: Repeated removal of Ob Nixilis cripples the primary win condition.
• Minimal artifact/enchantment removal: Relies solely on Feed the Swarm and planeswalkers to handle key threats.

Moderate

• Graveyard reliance: Crucible of Worlds, Soul Stair Expedition, and Skyclave Shade are vulnerable to Bojuka Bog effects.
• Slow board development: Limited early blockers make the deck susceptible to aggressive strategies.

Minor

• Life payment costs: Necropotence, Hatred, and fetchlands strain life totals against burn decks.
• Token overcommitment: Field of the Dead zombies are vulnerable to mass removal.

Most Important Cards:

• Ob Nixilis, the Fallen (Primary win condition)
• Cabal Coffers (Mana amplification)
• Urborg, Tomb of Yawgmoth (Mana fixing/coffers enabler)
• Hatred (Commander-damage finisher)
• Crucible of Worlds (Land recursion engine)
• Necropotence (Card advantage)
• Demonic Tutor (Tutoring)
• Field of the Dead (Alternate win condition)
• Ugin, the Spirit Dragon (Board control/finisher)
• Scroll Rack (Landfall synergy/card selection)

Attribute Ratings:

Speed: 6/10

• Capable of T5-T7 kills via Hatred or stacked landfall triggers but lacks fast combo finishes.

Resilience: 5/10

• Limited protection for Ob Nixilis beyond boots/greaves; struggles to recover from multiple wipes.

Consistency: 8/10

• Premium tutors (7+), land recursion, and black's draw power ensure reliable access to key pieces.

Interaction: 5/10

• Efficient creature removal (Deadly Rollick, Toxic Deluge) but minimal answers to noncreature permanents.

Rating Justification:

This deck demonstrates focused optimization with high consistency and a T5-T7 threat window but lacks the resilience and interaction density of top-tier lists. Its reliance on commander-centric combat damage and incremental value places it firmly in the optimized casual range.

Power level: 6.0 - 6.5